Tank for developing photographic plates.



F. A. STRKWSINE.

TANK FOR DEVELOPING PHOTOGRAPHIC PLATES.

APPLICATION HLwpEc. 7., 19x4.

,144:,008.. Patented June22, 1915.

W I ma 4. a E i if il/ bli E L; E E a I d f; WITHE SES- hwEnTorP r 7/? I f @M/ W I flTTORNEY THE.NORRIS PETERS CO., PHOT0-LITHO.. WASHINGTON, D. C.

FERN A. STBAVISINE, OF DETROIT, MICHIGAN.

TANK r03 DEVELOPING rnoroenarnrc PLATES.

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Specification of Letters Patent. Patented June 2 2, 1915.

Application filed. December 7, 1914:. Serial No. 875,770.

To all whom it may concern:

Be it known that I, FERN A. STRAwsINE, a citizen of the United States, residing at Detroit, county of Wayne, State of Michigan, have invented a certain new and useful Improvement in Tanks for Developing Photographic Plates, and declare the following to be a full, clear, and exact description of thesame, such as will enable others skilled in the art to which. it pertains to make and use the same, reference being had to the accompanying drawings, which form a part of this specification.

This invention relates to a tank for developing photographic plates.

It has for its object an arrangement whereby not only a plurality of plates may be simultaneously developed, but so arranged that one may easily examine all the plates to get the average time in which the images appear on the plates so as to determine the time that the plates should be left in the developing fluid.

In the drawings, Figure 1 is a plan view, a fragment only of the cover being shown. Fig. 2 is a vertical section with a part'of the inner wall of the tank shell broken away to show the devices behind.

a and I) represent two concentric walls forming a ring like shell to contain the developing fluid.

0 represents a spout which extends down the side of the shell a or what will be termed the tank shell a, and opens into the tank shell at the bottom through the port 6.

e designates a polygonal or endless frame, here shown as six-sided, although of course various numbers of sides may be used. The polygonal frame can be constructed in the following manner, although I do not limit myself to any special form of construction, as it is obvious that it may be made in various ways. It comprises a sheet of metal bent into polygonal shape and soldered together at its meeting ends to form an endless member. Rectangular openings f are cut out of each panel and strips g are soldered on to the shell at the meeting zones of the panels. These strips run vertically and both edges are spaced from the surface of the shell to form guides it. These strips 9 are located on both sides of the shell and one strip forms two guides, one for each of the two adjoining panels. The bottom edges of the panels are turned over, the middle portion 2' to the outside, and the two end portions j toward the inside. These form rests to hold the bottom of the plates. The guides A form the vertical run-ways for the plates. Three vertically projecting hooks Z are attached to the shell 120 degrees apart, and three brackets 70 are attached to the cover m 120 degrees apart. Ofcourse it is obvious that difl'erent numbers of brackets and hooks may be used, and hence I do not limit myself to any specific number. It will be understood that the cover 112 may be dropped down over the top of the tank with the brackets at one side'of the hooks Z. The cover may then be swung around and the hooks will thereby be automatically passed through the bracket, thereby connecting the cover with the shell so that the cover may be used to lift the polygonal frame. The cover itself is a ring having in cross section three sides of a rectangle. A handle or knob 'n. is attached to the center of the spider 0.

p designates a pipe which is in reality part of the tank, which may be attached to a source of water for washing the plates. This pipe 79 leads down the side of the tank and then turns and runs for a little distance concentrically with the wall of the tank so that the water is introduced into the tank substantially tangentially. This gives the water a swirling action best calculated to do its work in washing the plates.

This tank is especially well adapted for use in what is known as the factorial process of development. This process briefly is to insert a plate in a tank of developing fluid, then ascertain the length of time required for the image to appear on the plate.

This is done by lifting the plate frequently at the early stages of development for inspection. As soon as the length of time taken for the images to appear is learned, this is then multiplied by a predetermined factor common to the developer in use. The result secured is the length of time that the plate should be left in the developing fluid. Where a plurality of plates is used the time for the image to appear on each plate should be noted and the average taken and multiplied by the given factor. The plate holder that is above described is especially adapted for this factorial process because it will hold a large number of plates, as for instance, the design shown in the drawings will hold twelve plates as it has six panels, each of which holds two plates. Not only are the plates so arranged that they may be lifted with a minimum effort but they are so arranged that it may be easily determined by holding the plate holder up where the plates may be looked at just what time the images appear upon the plates.

What I claim is:

1. A developing tank, having in combination, a vertical ring like shell comprising an outer and inner wall forming a liquid containing space that may be fairly narrow and a polygonal frame adapted to be dropped into and withdrawn from said ring like shell.

2. A developing tank, having in combination, a ring like shell for holding the developing fluid, a polygonal frame for holding the plates adapted to be dropped into and withdrawn from said shell, a cover for said tank, and means for interlocking the cover with the frame so that the frame may be lifted with the cover.

3. A developing tank, having in combination, av ring like shell having an outer and inner wall, a polygonal frame provided with rests at the bottom and vertical guides, said frame adapted to be dropped into and removed from the said ring like shell.

1-. A developing tank, having in combination, a vertical ring like shell for holding the developing fluid, a polygonal frame or shell comprising a plurality of panels, each panel being provided with vertical guides at the sides and a rest at the bottom.

5. A developing tank, having in combination, a vertical ring like shell for holding the developing fluid, a polygonal frame comprising a plurality of panels, each panel provided at each side at its two vertical extremities with vertical guides and provided on each side with rests at the bottom.

6. A developing tank, having in co1nbi nation, a ring like vertical tank for containing the developing fluid, a polygonal frame for holding the plates, hooks attached to the frame and projecting upwardly, and a cover provided with depending brackets adapted to engage the hooks when the cover is partially rotated.

7. A developing tank, having in combination, a vertical ring-like shell comprising an outer and inner Wall, forming a liquid containing chamber that may be fairly narrow, and an endless frame provided with means for holding the members that are to be developed, said endless frame being shaped to be dropped into and withdrawn from the said ring-like shell.

In testimony whereof, I sign this specification in the presence of two witnesses.

FERN A. STRAWVSINE. lVitnesses:

STUART O. BARNES, VIRGINIA C. SPRATT.

Copier of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

